Benitoite
Formula: BaTi(Si3O9)
Species: Silicates – (Cyclosilicates)
Colour: Sapphire blue, white to colorless, pink
Lustre: Vitreous
Hardness: 6 – 6½
Specific Gravity: 3.65
Crystal System: Hexagonal
Member of: Benitoite group
Name: After the type locality, “as it occurs near the head waters of the San Benito River in San Benito County”, California, USA. It has been discovered in 1907 by a prospector who mistook it for sapphire.
Type Locality: California State Gem Mine, Santa Rita Peak, San Benito County, California, USA
Benitoite is barium titanium silicate. It is strongly dichroic, with blue, cut stones appearing blue or colorless when seen from different angles. It has strong color dispersion, making it nearly as brilliant as diamond. It is found in hydrothermally altered serpentine and in vein in schist. Gem-quality crystals are generally small, with cut stones seldom exceeding 5 carats. Its principal gem source is San Benito Mine, CA, where it was first discovered; pink crystals have been found at a nearby mine.